After the Soul Drinkers Space Marines are excommunicated, Imperial Agents are dispatched to destroy the once loyal chapter. Sarpedon, the leader of the Soul Drinkers, is hell-bent on discovering a way of curing his battle brothers of their mutations. Despite many false trails, Sarpedon has now stumbled upon the most tentative of leads, one which promises his troops a final redemption in the eyes of the God-Emperor--if they can survive long enough to reach him.